This document specifies the requirements for the quality identifiers that form part of an exchange of master data. These requirements supplement those of ISO 8000-110. The following are within the scope of this document: the syntax and semantics of quality identifiers to allow the unambiguous identification of the owner of the identifier and any restrictions on the use of the identifier; the principles of resolving quality identifiers to the data set they represent; the characteristics that define quality identifiers. The following are outside the scope of this document: the methods used for the creation of identifiers; the syntax of the query and of the response used in the resolution of identifiers; the methods used for the resolution of identifiers.